feat(ui): Layout improvements and KQL grammar tweak

[sushruth]

This PR introduces significant UI improvements including a resizable results pane and a collapsible sidebar, along with a minor grammar adjustment in kql-lezer.

Changes

@fossiq/ui

• Resizable Layout: Added a drag handle between the editor and results pane, allowing users to adjust the height of the results table.
• Collapsible Sidebar: The sidebar can now be collapsed to save space, showing only icons when collapsed.
• Visual Improvements:
  • Updated icons for better visual consistency.
  • Added emoji support for data sources in the sidebar.
  • Enhanced styling for the results table and scrollbars.
  • Refactored Layout component to support new structure.

@fossiq/kql-lezer

• Optional Query Expression: Modified the Query rule to make QueryExpression optional. This allows for queries that consist only of statements (like let statements) without a final expression.

Checklist

• UI changes verified visually (implicit in implementation)
• Grammar changes verified

---

This PR was created by an AI agent on behalf of @sushruth.

[Copilot]

Pull request overview

This PR enhances the UI with a resizable results pane and collapsible sidebar, while making the KQL grammar more flexible by allowing queries with only statements.

Changes:

• Added drag-to-resize functionality between editor and results panes with visual feedback
• Implemented collapsible sidebar with smooth animations and icon-only collapsed state
• Replaced generic icons with emoji representations for data sources
• Made QueryExpression optional in KQL grammar to support statement-only queries

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
packages/ui/src/utils/emojiGenerator.ts	New utility for generating deterministic emojis for data sources
packages/ui/src/styles/theme.css	Updated layout structure and added sidebar collapse/resize styling
packages/ui/src/icons/index.ts	Converted icons from filled to outline stroke style with new sidebar toggle icons
packages/ui/src/contexts/SchemaContext.tsx	Added emoji field to table schema
packages/ui/src/components/Sidebar.tsx	Implemented collapsible sidebar with toggle button and emoji support
packages/ui/src/components/ResultsTable.tsx	Added custom scrollbar styling and shadow to header
packages/ui/src/components/Layout.tsx	Refactored to support resizable panes and collapsible sidebar
packages/ui/src/App.tsx	Updated to use new Layout component API with separate editor/results panes
packages/ui/public/manifest.json	Updated app icons to match new outline style
packages/ui/public/index.html	Removed duplicate HTML file
packages/ui/index.html	Updated favicon to match new icon style
packages/kql-lezer/src/grammar/plugins/rules/query.ts	Made QueryExpression optional and improved code formatting

[Copilot]

The condition (virtualItems()[0]?.start ?? 0) > 0 is redundant. The spacer row should only render when there's an offset, which is already guaranteed by virtualItems().length > 0 since if there are virtual items and the first one exists, checking its start value is sufficient. The nullish coalescing with 0 means the condition would evaluate to 0 > 0 (false) when start is undefined, making the length check alone sufficient for the intended behavior.

Suggested change

	{virtualItems().length > 0 && (virtualItems()[0]?.start ?? 0) > 0 && (
	{virtualItems().length > 0 && virtualItems()[0]?.start > 0 && (

[Copilot]

The minimum (100) and maximum (600) height constraints are magic numbers. Consider extracting these as named constants (e.g., MIN_RESULTS_HEIGHT and MAX_RESULTS_HEIGHT) to improve code readability and maintainability.